Layard, P. R. G. (1972). Cost-benefit analysis: Selected readings. Penguin Education.
Chicago Style aipamenaLayard, P. R. G. Cost-benefit Analysis: Selected Readings. Harmondsworth, Eng. ; Baltimore: Penguin Education, 1972.
MLA aipamenaLayard, P. R. G. Cost-benefit Analysis: Selected Readings. Penguin Education, 1972.
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